When the coin hit the floor, the children gasped in surprise during a science class at Japan Freinet, a free school in Toshima Ward, Tokyo. They were experimenting to see which would fall first — the coin or a piece of paper of the same size.

Source: http://www.japantimes.co.jp/news/2016/02/05/national/japans-free-schools-offer-alternative-compulsory-education-accreditation-still-eludes/#.VrVl_VlUvqD